Abstract : A comprehensive set of experimental pressure, velocity and turbulence data are presented for two simple three-dimensional models having 2:1 and 3:1 elliptical transverse cross sections. The Lighthill displacement body concept is used to predict the pressure distributions over the models. The predicted pressure distributions are in good agreement with the measured pressure distributions. Around the corner regions over the major axes of the models the three-dimensional boundary-layer equations do not predict well the measured mean velocity distributions. In these regions the boundary layers are much thicker than the cross section dimensions and differences in curvatures between the flow and body surface are very large. However, over large areas of relatively flat body surfaces, the computed and measured mean velocity distributions are in good agreement.